In order to increase the available interior space of a motorized or towable vehicle such as a motor home or trailer, slide-out rooms can be made integral with the vehicle. When the vehicle is in transit, the slide-out room can be retracted and stored in the vehicle's interior with the exterior wall of the slide-out room approximately flush with the vehicle's exterior. As such, there is typically adequate space within the vehicle's interior to accommodate users in transit and remain within the standard width limitations imposed upon a vehicle. When the vehicle is parked and leveled, the slide-out room is then slid outward through an opening formed in a sidewall of a fixed room, increasing the internal accommodations.
As shown in FIGS. 1A and 1B, a typical slide-out room 20 usually includes a floor section 22, a roof section 24, a first sidewall section 26, a second sidewall section 28, and a third sidewall section 30. In the retracted position, the roof section 24 and the first 26 and second sidewall section 28 are concealed from exterior view, and the third sidewall section 30 forms a portion of the vehicle's sidewall. At the same time, the floor section 22 of the slide-out room 20 typically rests above a floor section 32 of a fixed room 34 and may form a portion of the usable interior floor during vehicle transit. Similarly, the roof section 24 of the slide-out room 20 may define the interior ceiling of that part of the vehicle during transit. The proximal ends of the roof section 24, first sidewall section 26, and second sidewall section 28, include stop walls 36. As used herein, “proximal” refers to the portion towards the vehicle body and “distal” refers to the portion away from the vehicle body. The stop walls 36 form a L-shaped configuration with the respective roof section 24, first sidewall section 26, and second sidewall section 28. The stop walls 36 engage the inner surface 38 of a respective sidewall section 40 of the fixed room 34 when the slide-out room 20 is fully extended, and thereby limit the travel of the slide-out room 20. Weather sealing material 42, as in compressible strip form, is located on the abutting surfaces of the stop walls 36 and/or inner surface 38 of the respective sidewall 40 of the fixed room 34.
A number of slide-out extension mechanisms are currently used to extend and retract the slide-out room. Typically, a slide-out extension mechanism 44 includes a pair of support rails 46 which telescopically extend and retract from a pair of channels 48. The support rails 46 are attached to the slide-out room 20 and the channels 48 are attached to the fixed portion of the vehicle, such as the fixed room 34, wherein the slide-out room 20 retracts and extends with the retraction and extension of the support rails 46. The support rails 46 may be driven hydraulically, pneumatically, electrically or various combinations thereof. In the fully extended position, the support rails 46 extend outwardly in a cantilevered manner and support the slide-out room 20. The slide-out room 20 is further supported by the stop walls 36 abutting the inner surface 38 of the respective sidewall section 40 of the fixed room 34.
Since the slide-out room 20 is nested within a portion of the fixed room 34, it is usually dimensioned smaller than the fixed room 34. Thus, when the slide-out room 20 is in an extended position, the floor section 22 of the slide-out room 20 is higher than the floor section 32 of the fixed room 34. Such stepped flooring 50 has frequently been found to be undesirable, inconvenient, and somewhat hazardous. For example, a person may easily overlook the step and trip or stumble if care is not taken. Furthermore, the step limits the positioning of furniture within the room, and the step makes it difficult to create an aesthetically pleasing floor appearance.
In response, slide-out rooms 100 have been developed with flooring having a flush upper surface (see FIGS. 2A and 2B). Unfortunately, a slide-out mechanism 102 can be overly complicated, expensive, and relatively heavy. In the vehicular environment, unnecessary weight reduces fuel economy and may lead to an overly cumbersome vehicle. However, if the slide-out extension mechanism 102 is insufficiently rigid, flexing may lead to misalignment of the drive mechanism such that the support rails 104 are no longer extended/retracted in synchronism. As a result, the slide-out extension mechanism 102 may become skewed or bind during the transit sliding action. Another problem arising from an insufficiently rigid structure is that the slide-out room 100 may exhibit “bouncing” when a dynamic load is imposed on a floor section 106. This can be particularly annoying when an occupant causes the slide-out room 100 to bounce while walking. In severe cases, cantilevering forces acting on the slide-out mechanism 102 may cause the sidewall sections 108, 110, 112 of the slide-out room 100 to sag and the floor section 106 to separate at their abutting edges. Furthermore, slide-out rooms using multiple floor panels, either completely removable or foldable on hinges, may buckle, warp, split, and crack and permit air drafts to rise from the floor through the gaps created by the misaligned panels.
Referring to FIGS. 3A and 3B, another feature which is growing in popularity is the application of a flush wall system. In the flush wall system, proximal ends of a first sidewall section 150, second sidewall section 152 and roof section 154 of the slide-out room 156 are flush with an interior surface 158 of a respective sidewall section 160 of a fixed room 162 when the slide-out room 156 is fully extended. Weather sealing material 164 is placed along the edge of an opening 166 formed in the sidewall section 160 of the fixed room 162 to form a seal between the rooms 156, 162. By doing away with the stop walls 36, the interior aesthetics is greatly improved. However, the load which was once supported by the stop walls 36 is now redirected to a slide-out extension mechanism 168. As shown in FIG. 3A, cantilevered support rails 170 flex from the added load, and as a result, the slide-out room 156 extends outwardly at a downward incline relative to the fixed room 162. In addition to the awkward appearance of the floor section 172 of the slide-out room 156 being inclined relative to a floor section 174 of the fixed room 162, the proximal end of the floor section 172 of the slide-out room 156 protrudes upwardly and a gap g is formed in the flooring. Furthermore, the seal between the rooms 156, 162 is ineffective because a gap is formed between the rooms 156, 162 due to the misalignment of the sidewall sections 150, 152 and roof section 154 of the slide-out room 156. Since vehicles of this type are often used during inclement weather, water, snow, and cold/hot air drafts may leak into the interior of the vehicle and create an inhospitable environment. In addition, certain vehicles such as medical and dental trailers require sterile environments.
In order to further increase the available interior space of vehicles, there is a growing trend to provide increasingly larger slide-out rooms. To accommodate larger sized slide-out rooms, the cantilevered support rails are lengthened. As a result of lengthening the cantilevered support rails and the increased weight of the slide-out room, the slide-out extension mechanism is more prone to flexing. In addition to the weight of the larger sized slide-out room, existing slide-out mechanism must support the additional weight resulting from furnishing the vehicle with amenities more commonly found in houses such as a microwave oven, refrigerator, dishwasher, washer/dryer, entertainment centers, desktop computer and related accessories. Furthermore, the slide-out extension mechanism must support larger sized furniture such a full size dining table, book shelves, cabinets and the like.
Another feature which is commonly available, particularly when relatively large slide-out rooms are utilized, is an automatically driven slide-out extension mechanism. The slide-out extension mechanism usually includes a motive device such as an electric motor to extend and retract the slide-out room. After the slide-out room is extended or retracted to the desired position, a brake is provided to positively fix the position of the slide-out room. In the event that the electric motor is inoperable, a manual override system is provided to retract or extend the slide-out room. The manual override system usually includes a crank handle which can be manually rotated to extend and retract the slide-out room. Before manually rotating the crank handle, it is usually necessary for an operator to release the brake. The brake is usually located underneath the vehicle in a relatively inaccessible location. Thus, an operator is required to go underneath the vehicle to remove the brake from the slide-out extension mechanism. Some slide-out extension mechanism are provided with a brake release lever pivotally mounted on an end of the brake. However, an operator must still go underneath the vehicle to rotate the brake release lever to the release position.
Thus, there remains a need for an improved slide-out extension mechanism which is capable of extending and retracting a slide-out room in a reliable, easily operated, and quiet manner that can be either incorporated into a vehicle body during manufacturing or retrofitted onto existing vehicle bodies. Furthermore, there remains a need to provide a slide-out extension mechanism which is relatively inexpensive and lightweight and yet sufficiently rigid.